Pump control



May 18, 1965 Filed May 16, 1963 V. A. BRUNSON ETAL PUMP CONTROL 2Sheets-Sheet l XNVENTORS. VIR61L A. BRUNSON I iirgil A. Brunson3,183,839 PUMP CONTROL and Harold L. Vandcn Hock, Grand Rapids, Mich,assignors to Blacitmer Pump Company, Grand Rapids, Mich, a company ofMichigan Filed May 16, 1963, Ser. No.280,841 4 Claims. (Cl. 103-21) Thisinvention relates to pumps and pump controls.

Positive displacement pumps'have been used extensively for pumpingliquids or fluids into confined spaces having ample storage capacity,such as tanks partially filled with air. However, the use of such pumpsfor pumping into systems having little or no storage capacity has notbeen completely satisfactory and has required relatively complicatedsystems. A major difliculty when pumping into a closed system havinglittle or no storage capacity is the difficulty of control of thepumping rate when the outlet of such system is throttled or closed.

Accordingly, the objects of this invention are to improve pumpingsystems, to simplify such systems, to provide such a system having a lowregulated pressure, substantially independent of pump speed, when thereis no flow in the discharge system and having a higher regulatedpressure when fiow exists in the discharge system, to provide a positivedisplacement pump with control means responsive to flow in the dischargesystem for adjusting valve means in the pump by air pressure to producesaid regulated pressures, to provide such a pump with a built-in aircontrolled bypass, to provide such a pump having superior simplicity,and to use air pressure, in a pump regulating valve, to select one oftwo fixed positions for the normally fixed end of a regulator springinlet port, a diaphragm closing the opening, a cap form-- ing a chamberover the diaphragm, and resilient means between the diaphragm and thevalve urging the valve toward its closed position. Control means areprovided communicating with the chamber and responsive to the flow inthe discharge system for supplying air under pressure to the chamber todrive the diaphragm toward the valve compressing the resilient meansbetween the diaphragm and the valve when fiow exists in the dischargesystem and to exhaust air from the chamber permitting the resilientmeans to expand and push the diaphragm away from the valve when there isno flow in the discharge system. The resilient means in itscompressedcondition maintains a high regulated pressure in the outlet port and inits expanded condition maintains a low regulated pressure in the outletport.

In accordance with the above, one feature of this invention resides inproviding the pump with a'built-in air controlled bypass. This producesa pump of superior simplicity, simplifying and lowering the cost of thesystem.

Another feature resides in providing pressure regulation at both lowpressure setting and the high pressure setting of the resilient means. alow regulated pressure, substantially independent of pump speed, whenthere is no flow in the discharge system and ahigher regulated pressurewhen flow exists in the discharge system.

Still another feature resides-in using air pressure to The pumpingsystem has 3,133,839 Patented May 18, 1965 ice select one of two fixedpositions for the normally fixed end of the resilient means.

The above and other objects and features of this invention will beappreciated more fully from the following detailed description when readwith reference to the accompanying drawings wherein:

FIG. 1 is a vertical section of a positive displacement pumpincorporating the built-in air controlled bypass; and

FIG. 2 is a schematic diagram of an improved pumping system constructedaccording to the invention.

Referring to the drawings, a rotary sliding vane pump 10 includes ahousing 11 having an inlet port 12 and an outlet port 13. These portsmay be fitted with threaded couplings or other means for attaching pipesto the pump. A shaft 14, extending transversely through the pump housing11, carries a circular cylindrical rotor 15 that fits within a rotorchamber 16 in the housing 11.

The rotor chamber 16 includes, as a wall thereof, an interior partition17 of the housing 11 having a cylidrical surface concentric with theshaft 14 at a radius equal to the radius of the rotor 15. Diametricallyopposite the partition 17, the rotor chamber 16 is formed by a portion18 of the bottom wall of the housing 11. This portion is concentric withrespect to the shaft 14 at a radius sufliciently greater than the radiusof the rotor 15 to provide pumping chambers in the space between therotor 15 and the wall portion 18.

The rotor 15 has a plurality of radial slots 19 extending parallel tothe shaft 14 to receive sliding vanes 26 which in cooperation with theexterior surface of the rotor 15 and interior surface of the chamber 16provides a series of pockets or chambers for transporting fluid from theinlet port 12 to the discharge port 13.

The rotor 15 has axially extending pockets 22 at the base of each of theslots 19 and the forwardly facing sides of the vanes 20 are grooved asindicated by the dotted lines 23 to form communicating passages betweenthe pockets or chambers formed ahead of the vanes 20 and the rotorpockets 22. The grooves 23 provide free communication between thepumping chambers ahead of the vanes 20 and the pockets 22 so that thevanes 20 may freely slide radially in the slots 19. Furthermore, byletting each of the pockets 22 communicate with the chamber ahead of thevane the pressure in the chamber is employed to hold the vane againstthe exterior wall of the rotor chamber 16.

To further assist the centrifugal force, as the rotor 15 turns, inthrowing the vanes 24) outwardly into contact with the wall of thechamber 16 a plurality of push rods 24 extending diametrically throughthe rotor 15 are provided so thatas one of a pair of vanes is pushedinwardly by contactwith a contracting portion of the chamber wall thediametrically opposite vane is pushed outwardly to keep it in contactwith an expanding portion of the wall of the chamber 16.

A bypass duct 25 leading from the outlet port 13 past a disk valve 26 tothe inlet port 12 is provided in the housing 11. The valve 26 controlsthe flow through the passage 25. The valve 26 is shown as a disk valvealthough other types such' as piston valves, ball seat valves or angularseat valves may be employed as long as the outlet pressure of the pumptends to open the valve. The

- disk valve 26 seats at 27 and is carried on a Valve guide a} the righthand disk 34 against a spring mounting 37 carried by the right hand endof the stem 35. A second spring mounting 38 is carried by the valve disk26 and the ends of a regulator coil spring 39 receive the mountings 37and 38, the regulator spring 39 being compressed between the respectivediaphragm disk 34 and the valve disk 26 urging the valve towards itsseat 27, i.e., toward its closed position.

The diaphragm stem 35 is axially slidable in an opening {it in the cup32. An adjustment nut 41 on the left hand end of the stem 35 exterior ofthe cup 32 acts as a stop limiting movement of the stem 35 to the rightby engaging the cup 32. A lock nut 42 maintains the adjusted position ofthe adjustment nut 41. The ring 36 and the cup 32 are held in place bymeans of screws 43, only one of which is shown, at an opening 44 definedby a wall of the housing 11. The opening 44, which is closed by thediaphragm 29, is in communication with the passage 25 and is between thevalve 26 and the inlet port 12.

The valve 26 is an air pressure adjusted relief valve, its body beingmade up of the ring 36, the cup 32 and that part of the pump housing 11at the valve 26, the valve seating at 27 in the pump. One of thefeatures of the pump resides in the built-in air controlled bypass whichsimplifies and lowers the cost of the system. The diaphragm 29 ismovable under the influence of air pressure (air supplied to the chamber33 through tubing 45) in opposition 'to the regulator spring 39 to aposition determined by engagement of the stop, i.e., adjustment nut 41,with the valve body to compress the regulator spring for high pressurevalve operation and is returned by the regulator spring in the absenceof the air pressure to permit low pressure valve operation. The stop 41is adjustable to select the desired high pressure. The stop 41 and truckpumpsystem. Such a system has little or no storage capacity. The airpressure adjusted relief valve 26 gives good control of the pumping ratewhen the outlet of such system is throttled or closed. Control means,hereinafter described, are provided which communicate with the chamber33 through the tubing 45 and are responsive to the flow in the dischargesystem for supplying air under pressure to the chamber 33 to drive thediaphragm toward the valve seat 27 compressing the regulator spring 39between the diaphragm disk 34 and the valve disk 26 when flow exists inthe discharge system and to exhaust air from the chamber 33 permittingtheregulator spring 39 to expand and push the diaphragm 29 away from thevalve. seat 27 when there is no flow in the discharge system. Theregulator spring 39 in its compressed condition maintains a highregulated pressure in the outlet port 13 and in its expanded conditionmaintains a low regulated pressure in the outlet port 13. One of thefeatures of the system resides in providing pressure regulation at boththe low pressure-setting and the high pressure charge system. -Anatherfeature resides in using air pressure to select one of two fixedpositions for the normally fixed end of the regulator spring 39.

The fuel oil delivery truck pump system is shown in 'FIG. 2. When thetruck driver arrives at a customers house, before he gets out of the cabhe puts the pump ill in gear and lets the truck motor run at idlingspeed. The pump 10, then willbe bypassing at a low pressure.

setting (system pressure about p.s.i.), since as hereinafter describedthere is no air pressure on the diaphragm 29. The driver pulls a hose 48from a reel 49 in a low pressure condition. It is preferred that therebe a certain minimum pressure always present in the system so that thehose 48 will wind on the reel 49 in an extended condition. A completelyflat hose, when wound on a reel, provides a restriction to thefiow onthe next usage if the entire'hoseis not removed from the reel. The aboveminimum pressure is obtained because the regulator spring 39 does not goto a completely relaxed position when air pressure is exhausted from thediaphragm chamber 33. When the driver puts the hoses nozzle 56 in thecustomers tank, he opens the nozzle 50. Flow of fuel oil through thesystem is sensed by means of a standard commercial pilot valve 51 whichopens an air valve 52 that supplies air under pressure through one endof the tubing to the diaphragm chamber 33 maintaining a high regulatedpump output pressure and supplies air under pressure through the otherend of the tubing 45 to an air cylinder 53. The air cylinder 53 has arod 54 which rocks a bell crank 55 clockwise as viewed in FIG. 2 aboutits pivot 56 when air is supplied to the cylinder 53 to actuate athrottle positioner on the truck motor to speed the motor up to normalpump speed. A return spring 57 returns the bell crank 55 to its positionshown in FIG. 2 when air is exhausted from the cylinder 53. When thedelivery is complete, the driver closes the nozzle 56 and immediatelythe truck motor drops back to idle speed and the air is exhausted fromthe diaphragm chamber 33 allowing the pump 10 to recirculate at lowpressure.

The inlet port 12 of the pump 11 communicates through a strainer 58 witha truck fuel oil tank 59 and the outlet port 13 of the pump 11 isattached to a pipe 60 which carries the fuel oil through an aireleminator 61, a meter 7 62 and the pilot valve 51 to a pipe 64communicating with the hose 48. The air eliminator 61 is provided with afloat-operated valve 65 which is mechanically connected to a float 66.At the start, the valve 65 is open exhausting any air under pressurethrough a vent pipe 67 to the atmosphere. When the fuel oil is pumpedthrough the pipe 60, it rises in the air eliminator 61 and air bubbleson top of the oil break and the air is exhausted to the atmosphere.Eventually, the oil rises to a point Where it lifts the float 66 closingthe valve 65. Air-free oil then flows into the meter 62. i

V The pilot valve 51 is a spring loaded poppet type check valve with anextended stem 68, carrying a member 69 which actautes the air valve 52.Being spring loaded by means of a spring 70, the pilot valve 51 providesa back pressure to the meter 62 and the air eliminator 61 which assistsin blowing air through the air eliminator vent 6'7. Without the backpressure, after the tank 59 is drained, air tends to run through themeter and the hose. The spring loaded pilot valve provides a barrier 71for the flow of air forcing it to go through the vent tube 67.Accordingly, the pilot valve 51 serves a double purpose. First, itprovides the back pressure to the meter 62 and to the air eliminator 61and, second,- it operates the air.

yalve 52. Air under pressure is supplied to the air valve 52 from atruck air supply tank 72 through a pressure regulator and filter 73(prevent moisture and dirt from getting into the air system). The airvalve 52 has two outlets, one being a vent pipe '74 open to theatmosphere and one being a pipe 75 communicating with the tubing 45, andone inlet pipe 76 in communication with the truck air supply tank 72.When. there is little or no fuel oil flow through the pilot valve 51,the member 69 closes the inlet pipe 76 and opens the vent pipe 74, andair is exhausted from the tubing 45 through the vent pipe 74. Thisexhausts air from the diaphragm chamber 33 and from theair cylinder 53.When there is fuel oil flow through the pilot valve 51, the oil pushesback the barrier 71 in opposition to the spring 79 and the member 69opens the inlet pipe I76and closes the vent pipe 74,

and air is supplied under pressure through the pipe 75 to the tubing 45.This supplies airunder pressure to the diaphragm chamber 33 and to theair cylinder 53.

Flow of fuel oil through the system is sensed by means of the pilotvalve 51 which, when there is oil flow, opens the air valve 52 that thensupplies air under pressure to the tubing 45, and which, when there isno oil fiow, closes the air valve 52 that then exhausts air from thetubing 45 to the atmosphere (no oil flow condition shown in FIG. 2). Theair under pressure is applied through the tubing 45 to the diaphragmchamber 33 forcing the diaphragm 29 and the end of the regulator spring39 remote from the valve disk 26 to a position fixed by the nuts 41 and42 on the threaded stem 35 and in this position the regulator spring 39holds the valve disk 26 closed until the desired high regulated pressureis reached at the pump discharge. If the pressure tends to rise abovesuch regulated pressure, the valve disk 26 lifts sufliciently to bypassthe excess fluid flow and maintains the preset pressure (preset byadjustment nut 41). The housing surrounding the valve disk 26 is dodesigned that little additional pressure is required to hold the valveopen for any bypass flow thereby holding a substantially constantmaximum pressure when the pump is operating at intermediate flow rates.When the air is released, as a result of the action of the pilot valve51 sensing a no flow condition in the pipe 60, the diaphragm 29 isallowed to move thus releasing the coil spring 39. The limit of travelof the diaphragm 29 is such that the coil spring 39 is not completelyreleased. In this position with the pump running at idling speed, thebypass valve 26 supplies enough back pressure to overcome the pilotvalve back pressure when the nozzle 50 is opened thus providing apressure drop across the pilot valve 51 to open the pilot valve.

In operation, with the nozzle 50 closed (condition of system as shown inFIG. 2), the pilot valve 51 senses a no oil flow condition, closing theair inlet 76 and opening the air vent 74 of the air valve 52. Air thenis exhausted from the diaphragm chamber 33 through the tubing 45, pipe75 and vent 74 of the air valve 52 to the atmosphere. The release ofhigh pressure air from the diaphragm chamber 33 permits the regulatorspring 39 to expand and push the diaphragm 29 away from the valve seat27, the regulator spring 39 holding the valve disk 26 closed until thedesired low pressure is reached at the pump discharge. This lowregulated pressure is substantially independent of motor or pump speed(one of the features of the system). If the pressure tends to rise abovesuch low regulated pressure, the valve 26 lifts sufliciently to bypassthe excess fluid flow and maintain the preset pressure. When the nozzle50 is opened, the pilot valve 51 senses oil flow, opening the air inlet76 and closing the air vent 74 of the air valve 52. Air then is suppliedunder pressure to the diaphragm chamber 33 from the air valve 52 throughthe pipe 75 and tubing 45. The air under pressure forces the diaphragm29 and the end of the regulator spring 39 remote from the valve disk 26to a position fixed by the nuts 41 and 42 on the threaded stem 35 and inthis position the regulator spring 39 holds the valve disk 26 closeduntil the desired high regulated pressure is reached at the pumpdischarge. The high regulated pressure is adjusted by turning the nuts41 and 42.

Accordingly, the air pressure adjusted relief valve of the inventioncontrols the pump 10 and, thus, controls the discharge system, therebeing in the pump control for the discharge system a pump having inletand outlet ports, a passage in the pump connecting the ports, valvemeans in the passage controlling the flow therethrough, and controlmeans responsive to flow in the discharge system for adjusting the valvemeans by air pressure to produce, when no flow exists in the dischargesystem, a low regulated pressure in the outlet port which issubstantially independent of pump speed and to produce, when flow existsin the discharge system, a regulated pressure in the out let port whichis higher than said low regulated pressure.

It is to be understood that the above description is illustrative ofthis invention and that various modifications thereof can be utilizedwithout departing from its spirit and scope.

Having described the invention, we claim:

1. A system for supplying liquid selectively at either of two controlledpressures comprising, in combination, a positive displacement pump, arelief valve for bypassing liquid from theoutlet to the inlet side ofthe pump to limit the pressure on the outlet side, a spring having oneend engaging the relief valve to bias the valve toward closed position,an abutment which supports the other end of the spring and which ismovable to change the closing bias of the valve, a line leading from theoutlet side of the pump which contains, in succession, an aireliminator, a meter and a valve for sensing flow which is biased towardclosed position and is opened by flow of liquid, and means actuated bythe flow-sensing valve for positioning the abutment to reduce theclosing bias of the relief valve when the flow of liquid in the line isreduced.

2. A system for supplying liquid selectively at either of two controlledpressures comprising, in combination, a positive displacement pump, arelief valve for bypassing liquid from the outlet to the inlet side ofthe pump to limit the pressure on the outlet side, a spring having oneend engaging the relief valve to bias the valve toward closed position,a chamber having a wall which supports the other end of the spring andwhich is expansible to change the closing bias of the valve, a fluidpressure-actuated control for regulating the speed of the pump, meansfor supplying fluid under pressure to the chamber and to the fluidpressure-actuated control, means for sensing flow of liquid in thesystem, and means actuated by the sensing means for changing thepressure of the fluid supplied to the chamber and to the fluidpressure-actuated control to reduce the closing bias of the valve andthe speed of the pump when the flow of liquid supplied by the system isreduced.

3. A system for supplying liquid selectively at either of two controlledpressures comprising, in combination, a positive displacement pump, arelief valve for bypassing liquid from the outlet to the inlet side ofthe pump to limit the pressure on the outlet side, a spring having oneend engaging the relief valve to bias the valve toward closed position,an abutment which supports the other end of the spring and which ismovable to change the closing bias of the relief valve, a second valvewhich is opened by flow of liquid through the system to sense flow ofliquid in the system, and means controlled by the second valve forpositioning the abutment to reduce the closing bias of the relief valvewhen the flow of the liquid supplied by the system is reduced.

4. A system as claimed in claim 3 wherein the abutment which supports anend of the spring is in turn supported by the wall of a chamber which isexpansible to change the closing bias of the relief valve, and whereinthe means controlled by the second valve positions the abutment bychanging the pressure in the chamber.

References Cited by the Examiner UNITED STATES PATENTS 1,367,452 2/21Bolton. 1,579,940 4/26 Iversen. 1,935,544 11/33 Delancey 103-422,160,028 5/39 Moore 103-42 2,280,291 4/42 Jaseph 103-42 2,364,489 12/44Taylor 103-42 2,409,975 10/46 Curtis 103-42 2,521,270 9/50 Vanni 103-422,625,108 1/53 Logan 103-42 2,671,409 3/54 Wright 103-42 2,683,418 7/54Smith 103-42 2,747,598 5/56 Wooldridge 103-42 (Other references onfollowing page) UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent No. 3,183,839 May 18, 1965 Virgil A. Brunson et al.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

In the grant, line 2, for "a company of Michigan," read assignors, bymesne assignments, to Dover Corporation of New York, N. Y., acorporation of Delaware, line 11, for "Virgil A. Brunson and Harold L.Vanden Hoek, their heirs" read Dover Corporation, its successors in theheading to the printed specification, lines 4 and 5, for "assignors toBlackmer Pump Company, Grand Rapids, Mich., a company of Michigan" readassignors, by mesne assignments, to Dover Corporation, New York, N. Y. acorporation of Delaware column 2, lines 20 and 21, for "cylidrical" readcylindrical column 3, line 68, for "Anather" read Another column 4, line35, for "eleminator" read eliminator line 48, for "actautes" readactuates column 5, line 21, for

"do" read so Signed and sealed this 26th day of April 1966.

(SEAL) Attest:

ERNEST ;W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

2. A SYSTEM FOR SUPPLYING LIQUID SELECTIVELY AT EITHER OF TWO CONTROLLEDPRESSURES COMPRISING, IN COMBINATION, A POSITIVE DISPLACEMENT PUMP, ARELIEF VALVE FOR BYPASSING LIQUID FROM THE OUTLET TO THE INLET SIDE OFTHE PUMP OF LIMIT THE PRESSURE ON THE OUTLET SIDE, A SPRING HAVING ONEEND ENGAGING THE RELIEF VALVE TO BIAS THE VALVE TOWARD CLOSED POSITION,A CHAMBER HAVING A WALL WHICH SUPPORTS THE OTHER END OF THE SPRING ANDWHICH IS EXPANSIBLE TO CHANGE THE CLOSING BIAS OF THE VALVE, A FLUIDPRESSURE-ACTUATED CONTROL FOR REGULATING THE SPEED OF PUMP, MEANS FORSUPPLYING FLUID UNDER PRESSURE TO THE CHAMBER AND TO THE FLUIDPRESSURE-ACTUATED CONTROL, MEANS FOR SENSING FLOW OF LIQUID IN THESYSTEM, AND MEANS ACTUATED BY THE SENSING MEANS FOR CHANGING THEPRESSURE OF THE FLUID SUPPLIED TO THE CHAMBER AND TO THE FLUIDPRESSURE-ACTUATED CONTROL TO REDUCE THE CLOSING BIAS OF THE VALVE ANDTHE SPEED OF THE PUMP WHEN THE FLOW OF LIQUID SUPPLIED BY THE SYSTEM ISREDUCED.